[strollfan]

Can't believe that is still going considering it was basically launched off the back of the success C4 had with Gordon Ramsey's Kitchen Nightmares about 20 years ago.

Is it C5's longest running programme?

Off the top of my head, The Gadget Show has run for a little bit longer, albeit through a frankly absurd amount of format changes and more recently name changes. 

The continuing Wright Stuff/Jeremy Vine block could also count, depending on how you see it, as it's essentially the same show in the same slot but with a change of host and name.